Host cytokine responses induced after overnight stimulation with novel M. tuberculosis infection phase-dependent antigens show promise as diagnostic candidates for TB disease

PLoS One. 2014 Jul 15;9(7):e102584. doi: 10.1371/journal.pone.0102584. eCollection 2014.

Abstract

Background: We previously identified Mycobacterium tuberculosis (M.tb) antigen-induced host markers that showed promise as TB diagnostic candidates in 7-day whole blood culture supernatants. The aim of the present study was to evaluate the utility of these markers further, and cross-compare results with short-term antigen stimulated and unstimulated culture supernatants.

Methods: We recruited 15 culture confirmed TB cases and 15 non-TB cases from a high-TB endemic community in Cape Town, South Africa into a pilot case-control study from an on-going larger study. Blood samples collected from study participants were stimulated with 4 M.tb antigens that were previously identified as promising (ESAT6/CFP10 (early secreted), Rv2029c (latency), Rv2032 (latency) and Rv2389c (rpf)) in a 7-day or overnight culture assay. Supernatants were also collected form the standard QuantiFERON In Tube (QFT-IT) test. The levels of 26 host markers were evaluated in the three culture supernatants using the Luminex platform.

Results: The unstimulated levels of CRP, Serum amyloid P (SAP) and serum amyloid A (SAA) and ESAT-6/CFP-10 specific IP-10 and SAA were amongst the best discriminatory markers in all 3 assays, ascertaining TB with AUC of 72-84%. Four-marker models accurately classified up to 92%, 100% and 100% of study participants in the overnight, 7-day and Quantiferon culture supernatants, respectively, after leave-one-out cross validation.

Conclusion: Unstimulated and antigen-specific levels of CRP, SAA, IP-10, MMP-2 and sCD40L hold promise as diagnostic candidates for TB disease in short-term stimulation assays. Larger studies are required to validate these findings but the data suggest that antigen-specific cytokine production and in particular mutimarker biosignatures might contribute to future diagnostic strategies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antigens, Bacterial / immunology
  • Biomarkers / blood
  • Cytokines / blood*
  • Female
  • Humans
  • Interferon-gamma Release Tests
  • Male
  • Mycobacterium tuberculosis / immunology*
  • Pilot Projects
  • ROC Curve
  • Tuberculosis, Pulmonary / blood*
  • Tuberculosis, Pulmonary / diagnosis
  • Tuberculosis, Pulmonary / immunology
  • Young Adult

Substances

  • Antigens, Bacterial
  • Biomarkers
  • Cytokines

Grant support

The authors acknowledge the EDCTP (grant IP. 09.32040.011), EC FP7 NEWTBVAC contract no. HEALTH.F3.2009 241745, EC FP7 EURIPRED contract no. INFRASTRUCTURES.2012.1 312661 and EC FP7 VACTRAIN (the text represents the authors’ views and does not necessarily represent a position of the Commission who will not be liable for the use made of such information). Paulin Essone is funded by “Agence nationale des bourses du Gabon”. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.